Spinning fibers



July 25, 1967 A, T A G 3,332,110

SPINNING FIBERS Filed Aug. 23, 1965 2 Sheets-Sheet 1 MZZMMAM A ltorneys July 25, 1967 A. STRANG 3,332,110

SPINNING FIBERS Filed Aug, 2 1965 2 Sheets-Sheet 2 13. FIG.2

\/Us I 4 W FIG.3 13 I Attorneys United States Patent 3,332,110 SPINNING FIBERS Alastair Strang, Styvechale, England, assignor to Courtaulds Limited, London, England, a British company Filed Aug. 23, 1965, Ser. No. 481,516 Claims priority, application Great Britain, Aug. 25, 1964, 34,699/ 64 4 Claims. (Cl. 18-8) This invention relates to apparatus and methods for spinning man-made fibers and is particularly concerned with apparatus and methods for spinning bicomponent composite fibers.

Bicomponent composite fibers have been produced by feeding two different spinning compositions, referred to hereinafter as dopes, separately to the same jet orifice,

- whereby fibers of asymmetric cross-sectional composition are obtained. One method by which such bicomponent composite fibers may be produced uses two concentric circular channels divided by a ridge above which ridge the jet orifices are located. The two channels are fed with two different dopes which are thus fed simultaneously and separately to the jet orifices. Such an arrangement has the disadvantage that control of the flow of dope to the individual orifices is imperfect, and fibers of uniform composition are not readily obtained. Moreover, the arrangement does not lend itself readily to the design of the spinning head with a very large number of jet orifices, such as the types which can usefully be employed in the production of tows and staple fibers by wet spinning methods.

According to this invention a spinning head for the production of bicomponent composite fibers comprises a jet head having a multiplicity of jet orifices arranged in a series of rows which may be straight or curved and a jet feed apparatus having a corresponding number of feed channels each of which channels is separated from at least one adjacent channel by a ridge beneath a row of jet orifices, and in which each channel of each adjacent pair of channels is fed from at least one end thereof separately from the other.

In this specification, where it is stated that the rows of jet orifices are above the corresponding ridges, or that the ridges are below or beneath the rows of jet orifices, the words above and below or beneath do not signify a spatial relationship, but merely describe the relative positions of the elements concerned, with the apex of each ridge considered uppermost. It will be understood that the spinning head may be employed in any desired position.

The spinning head may be of any suitable shape, for example, it may be circular, or rectangular in plan. The jet orifices may be disposed in rows radially, or may be in straight rows parallel with one another. Any other arrangement of the rows of jet orifices may, however, be adopted consistent with the requirement that each row has ends and that the channels feeding them must be capable of being fed from at least one end thereof. Thus, in a circular spinning head with radial rows of jet orifices the corresponding channels are also radially :disposed with the dividing ridges located below the rows of jet orifices. In this case the channels are fed from their peripheral ends. If the rows of jet orifices are straight and parallel to one another the channels corresponding to them are also straight and parallel to one another and may suitably be fed from both their ends.

In any feeding arrangement it is important that at any point along the dividing ridges the pressures of the [dopes on either side of those ridges should be substantially identical, since it is important in order to obtain fibers of constant cross-sectional composition that the flow of the two diflFerent dopes through the orifices should be controlled accurately at all points on the spinning head.

The channels with their dividing ridges and corresponding rows of jet orifices may be arranged continuously side by side around or along the face of the spinning head, or if desired, they may be separated into groups by sectors or sections without jet orifices.

Feeding the dopes to the channels may be accomplished in any suitable manner which allows that no two adjacent channels contain dope of the same composition. Thus, for example, in a circular spinning head adjacent channels may be fed from two annular feed chambers located at their outer ends and communicating respectively with the one and the other and so on throughout the periphery of the spinning head. Where parallel channels are employed, the feed chambers may be located at the end of the channels, each feed chamber communicating with alternate channels, It is not satisfactory to feed one 'dope from one end of the channels and the other dope from the other end of alternate channels, since this introduces pressure differentials along the channels which are not in the same sense.

While the spinning head according to the invention may be of any desired size, its advantages in overcoming the difficulties previously encountered are only seen where a very large number of jet orifices is required. Thus, such difficulties are not met in spinning heads having substantially less than one thousand jet orifices and the invention is particularly adapted for use-with a spinning head having a considerably larger number than this. The practical limit to the number of jet orifices which may be employed is determined only by the shape and size of the orifices and of the jet head, together with the required minimum orifice spacing.

The apparatus of the invention may be used for spinning man-made fibers of substantially any kind, for example, by dry-spun or melt-spun techniques, but is particularly adapted to the production of bicomponent fibers by wet-spun methods, which have latent crimping properties which may be developed by differential shrinking of the components. The invention also includes the process of making bicomponent composite fibers by means of the spinning head of the invention and bicomponent composite fibers made by that process.

The invention will be further described by way of example with reference to the accompanying drawings.

In the drawings:

FIGURE 1 is an exploded part perspective, part sectional representation of a circular spinning head according to the invention with radial channels.

FIGURE 2 is a true section through the plane of radius II of the feed apparatus of the spinning head shown in FIGURE 1, and

FIGURE 3 is a true section through the plane of radius III of the feed apparatus of the spinning head shown in FIGURE 1.

For simplicity only half of the apparatus has been shown in each of the figures.

Referring to the drawings, a jet head 1 with radially disposed jet orifices 2, is clamped by a retaining ring 3 to a skirt 4 around a feed plate 5 provided with grooved channels 6 and 6' separated by dividing ridges 7, 7', (for clarity only representative of the multiple elements are indicated by number) so that a row of jet orifices 2 is immediately above a dividing ridge 7 or 7'. The grooved channels 6 are open at their outer ends to an annular feed chamber 8 between the skirt 4 and a backing plate 9 on the feed plate 5, while the grooved channels 6' are closed at their outer ends to the chamber 8 but are open instead at their outer ends to a second feed chamber 10 between the feed plate 5 and the backing plate 9. A closure plate 11 completes the assembly by providing the outer wall of the feed chamber '8, and pipes 12 and 13 respectively are provided for the introduction of the two dopes into the feed chambers 8 and 10.

FIGURES 2 and 3 respectively show the arrangement of the feeds to channels 6 and 6' enabling dopes A and B to pass freely into alternate similar grooves, obtaining thereby the required distribution. In use, the two dopes A and B are fed under controlled conditions through the pipes 12 and 13 to the feed chambers 8 and 10 whence they pass to channels 6 and 6' respectively and thence together from the dividing ridges 7 and 7 to the jet orifices 2,

I claim:

1. A spinning head for the production of bicomponent composite fibers which comprises a jet head having a multiplicity of jet orifices arranged in a series of discontinuous rows and a jet feed apparatus having a corresponding number of feed channels having ends each of which channels is separated from at least one adjacent channel by a ridge directly beneath a row of jet orifices, in combination with means for feeding each channel of each adjacent pair of channels from at least one end thereof separately from the other.

2. A spinning head as claimed in claim 1 in which the jet head has not less than one thousand jet orifices.

3. A spinning head as claimed in claim 1 in which the jet orifices are arranged in radial rows about a center, and the feed channels are fed from the outer ends thereof.

4. A spinning head as claimed in claim 1 in which the feed channels are arranged continuously side by side on the face of the jet head, with dividing ridges and associated rows of jet orifices between each pair of feed channels.

References Cited UNITED STATES PATENTS 2,798,252 7/ 1957 Cummings 188 3,166,788 1/1965 Kiser 18-8 3,176,342 4/1965 Davis -188 3,176,346 4/1965 Brazelton 18-8 3,182,106 4/ 1965 Yoshimasa Fujita et al.

18-8 XR 3,182,352 5/1965 Baer 18-8 3,224,041 12/1965 Reynolds 188 WILLIAM J. STEPHENSON, Primary Examiner. 

1. A SPINNING HEAD FOR THE PRODUCTION OF BICOMPONENT COMPOSITE FIBERS WHICH COMPRISES A JET HEAD HAVING A MULTIPLICITY OF JET ORIFICES ARRANGED IN A SERIES OF DISCONTINUOUS ROWS AND A JET FEED APPARATUS HAVING A CORRESPONDING NUMBER OF FEED CHANNELS HAVING ENDS EACH OF WHICH CHANNELS IS SEPARATED FROM AT LEAST ONE ADJACENT CHANNEL BY A RIDGE DIRECTLY BENEATH A ROW OF JET ORIFICES, IN COMBINATION WITH MEANS FOR FEEDING EACH CHANNEL OF EACH ADJACENT PAIR OF CHANNELS FROM AT LEAST ONE END THEREOF SEPARATELY FROM THE OTHER. 